Position Of Clavicle Research Articles

Position of scapula and clavicle in acute acromioclavicular joint dislocations: depressed scapula or elevated distal clavicle?

Position of scapula and clavicle in acute acromioclavicular joint dislocations: depressed scapula or elevated distal clavicle?

Dose coverage and breath-hold analysis of breast cancer patients treated with surface-guided radiotherapy

BackgroundSurface-guided radiotherapy (SGRT) is used to ensure a reproducible patient set-up and for intra-fraction motion monitoring. The arm position of breast cancer patients is important, since this is related to the position of the surrounding lymph nodes. The aim of the study was to investigate the set-up accuracy of the arm of patients positioned using SGRT. Moreover, the actual delivered dose was investigated and an extensive breath-hold analysis was performed.Methods84 patients who received local or locoregional breast radiation therapy were positioned and monitored using SGRT. The accuracy of the arm position, represented by the clavicle position, was studied on the anterior–posterior kV-image. To investigate the effect of changes in anatomy and patient set-up, the actual delivered dose was calculated on cone-beam CT-scans (CBCT). A deformable registration of the CT to the CBCT was applied to deform the structures of the CT onto the CBCT. The minimum dose in percentage of the prescribed dose that was received by 98% of different CTV volumes (D98) was determined. An extensive breath-hold analysis was performed and definitions for relevant parameters were given.ResultsThe arm position of 77 out of 84 patients in total was successful, based on the clavicle rotation. The mean clavicle rotation was 0.4° (± 2.0°). For 89.8% of the patients who were irradiated on the whole-breast D98 was larger than 95% of the prescribed dose (D98 > 95%). D98 > 95% applied for 70.8% of the patients irradiated on the chest wall. Concerning the lymph node CTVs, D98 > 95% for at least 95% of the patients. The breath-hold analysis showed a mean residual setup error of − 0.015 (± 0.90), − 0.18 (± 0.82), − 0.58 (± 1.1) mm in vertical, lateral, and longitudinal direction, respectively. The reproducibility and stability of the breath-hold was good, with median 0.60 mm (95% confidence interval (CI) [0.66–0.71] mm) and 0.20 mm (95% CI 0.21–0.23] mm), respectively.ConclusionsUsing SGRT we were able to position breast cancer patients successfully, with focus on the arm position. The actual delivered dose calculated on the CBCT was adequate and no relation between clavicle rotation and actual delivered dose was found. Moreover, breath-hold analysis showed a good reproducibility and stability of the breath-hold.Trial registration CCMO register NL69214.028.19.

Radiologic features of dropped head syndrome in the overall sagittal alignment of the spine.

Dropped head syndrome (DHS) is a rare clinical entity which is defined as a chin-on-chest deformity in the standing or sitting position, resulting from sagittal imbalance of the cervical region. The purpose of the present study was to clarify the radiologic features of DHS in the overall sagittal alignment of the spine. We also investigated the changes in sagittal alignment after correction surgery for DHS. Twenty DHS patients [1 male and 19 female, with an average age of 78.9years (range 59-88)] with a main complaint of horizontal gaze disorder were enrolled in this study. Spino-pelvic lateral radiographs in the free-standing clavicle position were taken of all patients. Parameters such as sagittal vertical axis (SVA), C2-7 angle, clivo-axial angle (CAA), C2-7 SVA, T1 slope, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) were measured, and the radiologic features of DHS in the overall sagittal alignment of the spino-pelvis were investigated. Eight patients underwent correction surgery, and the parameter changes between pre- and post-operative radiographs were also examined. DHS appeared to have two distinct types: SVA+ and SVA-. Seven of 20 cases were SVA+, and 13 were SVA-. The radiologic parameters in which we found statistically significant differences between the groups were: 80.2±68 and -44.5±40 (SVA), 42.1±16.8 and 18.4±11.4 (T1 slope), and 21.1±19.2 and 44.2±19.8 (LL) in SVA+and SVA-, respectively. After surgical intervention, T1 slope and LL appeared to approach normal in the SVA- group, because compensation at downward spine was no longer necessary. In SVA+group, although the patients gained horizontal gaze after surgery, abnormality of the sagittal alignment in the whole spine remained, because compensation in the thoracic and lumbar spine was still insufficient. The present study has indicated that radiologic feature of DHS in the sagittal alignment of the overall spino-pelvis can be categorized into two types: SVA+ and SVA-.

Repeatability Test of C7 Plumb Line and Gravity Line on Asymptomatic Volunteers Using an Optical Measurement Technique

Prospective cohort evaluation of C7 plumb line (C7PL) and gravity line (GL) in different standing positions in asymptomatic volunteers. To evaluate the repeatability of C7PL and GL in different standing positions using an optical method. Both C7PL and GL have been used to assess spinal balance. However, due to extensive radiation exposure, the measurement repeatability for both C7PL and GL has never been systematically determined. Thirty asymptomatic adult volunteers were enrolled in this study. Two optical markers were attached to the skin overlying the spinous processes of C7 and S1. Volunteers were instructed to stand on a force plate with their arms in 3 different positions, clavicle, supported, and neutral, for posteroanterior (PA), and lateral views. Digital photos were taken for 12 times for each position. The GL position was displayed on a computer in real time. The distance from the C7 marker to S1 marker (C7-S1) and the distance from the GL to the S1 marker (GL-S1) were measured in both PA and lateral views. The repeatability on a single subject was defined as the standard deviation of the 12 repeated measurements for each standing position. In the PA view, the repeatability of both C7PL and GL was 3 to 4 mm in all 3 standing positions (all P > 0.05). In the lateral view, the repeatability of C7PL increased from 6 to 8 mm whereas GL remained low at 3 to 4 mm. The GL repeatability was significantly better than that of C7PL in all 3 lateral positions (all P < 0.05). The standing position did not significantly affect repeatability for both C7PL and GL. C7PL had approximately 1-cm posterior shift in the supported position and 2-cm posterior shift in the clavicle position. The effect of various radiographic positions was less than 1 cm for all 3 standing positions in the GL measurement. The GL measurement was highly reproducible in both PA and lateral views. The repeatability was similar between C7PL and GL despite the standing positions in the PA view. The repeatability of GL was better than that of C7PL in all 3 standing positions in the lateral view. The effect of standing positions was much less in GL than in C7PL.

Optimal Standing Radiographic Positioning in Patients with Sagittal Imbalance

Study Design: This is a review of the literature about radiographic positioning for patients with sagittal imbalance. Objectives: We wanted to verify the optimal radiographic positioning for patients with sagittal imbalance. Summary of Literature Review: The standing lateral whole spine radiograph for identifying the sagittal alignment has a different value for the SVA according to the radiographic positioning. Materials and Methods: This is a review of the literature. Results: The fists-on-the clavicle position or the cross-arm position not only represents a functional standing position, but it also causes a less negative shift of the SVA in patients with sagittal imbalance. Both the extended hip and knee positions are necessary to exclude a compensation mechanism of the lower extremity. Conclusions: The optimal radiographic positioning is essential to examine the degrees of sagittal imbalance.

Which Lateral Radiographic Positioning Technique Provides the Most Reliable and Functional Representation of a Patient’s Sagittal Balance?

Prospective nonscoliotic cohort evaluation of the effects of various positions for obtaining standing lateral thoracolumbar radiographs. The purpose of this study was to compare the effects of various upper extremity positions on thoracolumbar sagittal spinal alignment. The standing position used to capture a lateral plane radiograph can have marked effects on measurements of sagittal spinal alignment and may compound the variability between measurements from successive radiographs. Twenty-two healthy female adolescents performed 3 repeated trials of 4 standing positions in a motion analysis laboratory. The positions included: (1) relaxed standing with arms at sides (CONTROL), (2) standing with fists overlying ipsilateral clavicles (CLAVICLE), (3) active shoulder flexion to 30 degrees with elbows extended (30 ACTIVE), and (4) passive shoulder flexion to 30 degrees with hand supports (30 PASSIVE). Sagittal alignment of the spine was described by kyphosis, lordosis, and the sagittal vertical axis (SVA), all of which were measured from the positions of reflective markers attached to the surface of the back and pelvis. Differences between alignment measures obtained for each of the 3 radiographic positions relative to the functional position (CONTROL) were calculated. Mean differences were then compared between positions using repeated measures ANOVAs (alpha = 0.05). Relative to the CONTROL position, all other positions resulted in negative shifts in SVA (range = -1.1 cm- -4.6 cm), decreased kyphosis (range = -1 degrees- -3 degrees), and increased lordosis (4 degrees for all positions). The shift in the SVA with the 30 PASSIVE position was significantly less than the other 2 positions (P < 0.05) and demonstrated the least variability. Standing with the hands supported while flexing the shoulders 30 degrees during positioning for lateral spinopelvic radiographic acquisition resulted in an SVA and measures of sagittal plane curvature that were comparable with a functional standing position with arms at the side. This seems to be the best way to move the arms anterior to the spine with the least effect on overall sagittal balance.

Is There an Optimal Patient Stance for Obtaining a Lateral 36” Radiograph?

Scoliosis patients were prospectively x-rayed in three positions with independent analysis. To determine if one positioning technique provides superior visualization of critical landmarks (C7, T2, T12, L5-S1) and to determine any position dependent variations in regional measures or sagittal balance. Different techniques for positioning patient's arms are used for 36" lateral radiograph with no data on relative effects. A total of 25 scoliosis patients were prospectively studied with 36" lateral radiographs in three positions varying arm location (straight out, partially flexed, and the "clavicle" position). Films were analyzed independently by three surgeons. Vertebral landmarks were scored for clarity; and lordosis, kyphosis, and global balance were analyzed. Statistical analysis was done with a General Estimating Equations model. The overall visualization score for the clavicle position was superior to either the 60 degrees or 90 degrees positions (clavicle vs. 60 degrees, P < 0.0001; clavicle vs. 90 degrees, P < 0.0003). Analysis of vertebral landmarks showed significantly better visualization of T2 with clavicle versus 90 degrees (P < 0.047), better visualization of T12 with clavicle versus either 60 degrees (P < 0.006) or 90 degrees (P < 0.049), and better visualization of L5-S1 with clavicle versus 90 degrees (P < 0.02). Regional measures showed no differences, but sagittal balance was significantly more positive in the 60 degrees position than either clavicle (P < 0.04) or 90 degrees (P < 0.015). The clavicle position for obtaining lateral 36" radiographs produces significantly better overall visualization of critical vertebral landmarks. Regional measures do not differ between the three positions, but global balance is more positive with the 60 degrees position. Clinically, the clavicle position may result in more accurate radiographic measures and may minimize repeated radiograph exposures.